Interval timer



y 1, 1963 P. A. MARTIN 3,090,249

INTERVAL TIMER Filed Oct. 31, 1957 Arweuror United States Patent;

3,090,249 INTERVAL TIMER Paul A. Martin, Newton, Iowa, assignor to TheMaytag Company, Newton, Iowa, a corporation of Delaware Filed Oct. 31,1957, Ser. No. 693,744 2 Claims. (Cl. 74--568) This applicationconstitutes a continuation-in-pa-rt of the Paul A. Martin application,Serial No. 621,681, filed November 13, '1956 and issued November 8,1960, as Patent No. 2,959,646 for Indexing Interval Timer and assignedto the assignee of the instant invention.

This invention relates to a timer apparatus for sequentially energizingor deenergizing one or more electric circuits. It specifically relatesto a sequential controlling mechanism with which the programming of oneor more sequentially operated circuits may be relatively adjusted withrespect to the programming of another group of sequentially operatedcircuits. The specific timing apparatus disclosed hereinafter isparticularly suitable for controlling the operation of a combinationwasher-drier in which either or both of the washing and dryingoperations may be preset to operate over predetermined timed intervals.

The timer mechanism disclosed hereinafter incorporates a motor drivenshaft to which one or more cams regulating the washing operation of acombination washer-drier are affixed and to which one or more main camsregulating the drying operation in this combination washer-drier arealso 'atfixed. In the disclosed embodiment of this timer mechanism, themain cams regulating the drying operation are provided with secondarycams or cam segments which are revolubly mounted adjacent the main drycams on the timer drive shaft.

Manual variation of the secondary cams to vary the effective camprofiles of the drying cams thereby adjusting the programming betweenthe wash and dry circuits is achieved by movement of a control leverwhich rotates the secondary cams relative to the main drier cams througha differential gear mechanism mounted on the timer drive shaft. Bycoordinating the positioning of the timer cams with appropriate indiciacorresponding to the functions controlled by those cams as indicated bythe positioning of the control lever and the timer control knob attachedto the timer drive shaft, a washer-drier incorporating this inventionmay be preset to control and indicate the duration of the wash and drycycles, the starting and stopping points for the machine and the precisestage being performed by the machine as it progresses through itscomplete fabric treatment operational cycle.

In the accompanying drawing:

FIGURE 1 is an enlarged fragmentary view of a timer forming the basisfor the invention of this application;

FIGURE 2 is a view taken along line 2--2' of FIG- URE 1; and,

FIGURE 3 is a view taken along line 33- of FIG- URE 2.

The subject matter forming the basis for the aforementioned Martinapplication Serial No. 621,681, now Patent No. 2,959,646, is referred tofor a more complete description of the basic operation of a timer ofthis type as used in conjunction with a washer-drier.

A modified construction forming the primary disclosure for the instantinvention is shown in FIGURES 1-3. From a comparison of FIGURES 3 ofU.S. 2,959,646 and 2 herein it will be apparent that the sole differencein the construction details of the two embodiments shown in thesefigures resides in the epicyclic differential gear package locatedbetween the panel member 15 and the front timer plate 46. The remainingportions of the timer construction, circuitry connected to this timerconstruction and the general overall mode of operation for theembodiment of FIGURES 12 are identical to that of the first embodimentin U.S. 2,959,646 so that the same reference numerals will be used inthe explanation of this second embodiment wherever possible. Thedifferences in construction and detailed operation will be set forth,however.

Looking now at FIGURE 2, it will be seen that the timer drive shaft 36,through cooperation of flat 63 located on that timer shaft, mounts thesun or drive gear 131 which is maintained in place on shaft 36 by meansof the spacer member 84, lock nut 83 and the timer control knob 86.

The sleeve 45 mounting the auxiliary dry cams 54 and 55 is provided witha driven gear 133 which may be aflixed to sleeve 45 in any suitablemanner. These gears 131 and 133 not only drive the auxiliary dry cams 54and 55 as well as providing a means for adjusting the angulardisplacement between auxiliary cams 54 and 55 with respect to the maindry cams 42 and 41, respectively, but also serve, in this embodiment, toregulate the axial positioning of the planetary differential unit ofwhich these gears are a part.

The differential unit also includes a pair of planetary pinions 13-5meshing with drive gear 131 and a second pair of planetary pinions 136meshing with the driven gear 133. These two sets of planetary pinions135 and 136 are freely revolub-le on the cross pins 137 which penetratethe front and rear washer-shaped planetary carriers 138 and 139,respectively, and are provided with enlarged ends to sandwich theseconfining washers and planetary pinions together.

It will be seen from FIGURE 2 that the central portions of the confiningwashers 138 and 139 overlap gears 131 and 133, respectively, so as toprovide a means for maintaining these pinions in mesh with theirrespective cooperating gears even though sleeve 45, together with shaft36, may be moved axially to actuate line switch in response to axialmanipulation of control knob 86.

The planetary pinions are encircled by and mesh with a nonrotatable ringgear 141 provided with a pair of diametrically opposed ears 142 whichreceive in a sliding fit the guide .pins 143 attached to the front timerplate 46. This construction allows ring gear 141 to be moved axiallywithout being revoluble.

A second adjustable ring gear member 145 encircles and meshes with theplanetary pinions 136. This ring gear is connected to the manuallyadjustable lever 78 which penetrates panel member 15.

Lever 78, as shown in FIGURE 1, protrudes through back panel member 15in an arcuate slot 148 positioned above knob 86 and extending slightlyover 90? in arcuate extent. Separate dry time setting indicia 149 islocated adjacent this slot 148 to indicate the dry time settingpositions of lever 78 therefor.

Between the nonrotatable ring gear 141 and the adjustable ring gear 145is a ring of friction material 151 which is cemented to the nonrotatablering gear :141 and engages the contiguous face of adjustable ring gear145. A pair of wave washers 152 adjacent ring gears 141 and 145 bearagainst the confining washers 138 and 139 to maintain the adjustablering gear 141 in a frictional contact with the friction material 151 soas to provide a means for positioning these ring gears in a verticalposition and maintaining a sufiicient contact force on the adjustablering gear 145 to keep that latter member from rotating during therotation of timer shaft 36. In spite of the use of friction material151, however, adjustable lever 78 may be easily moved relative tofriction material 151 due to the relatively small frictional forcesproduced by this sandwich unit. It should be noted that while a pair ofwave Washers 152 have been used in this illustrative unit forsymmertical positioning of ring gears 141 and 145 on their respectiveengaging gears, other various biasing devices may also be used torestrict rotation of lever 78 without departing from the principle ofoperation basically disclosed in the accompanying figures.

Now with reference to the presetting and operation of the timermechanism shown in FIGURES 1-3, it will be noted that the positioning oflever 78 in FIGURE 1 corresponds identically to that setting of lever 78shown in FIGURE 2 of U.S. 2,959,646. The difference between these twofigures is in the location of the setting lever 78 with respect to thedry timer indicia 122. In FIGURE 2 of U.S. 2,959,646, the setting lever78 may be oscillated throughout an 180 are immediately adjacent the drytimer portion of indicia 122 whereas in FIGURE 1 the setting lever 78may be oscillated throughout an arc of approximately 90 adjacent theindicia 149 located above timer control knob 86.

The general setting operation and overall mode of operation betweenconstructions of FIGURE 2 of 2,959,646 and FIGURE 1 is substantiallyidentical. For example, if lever 78 is moved to the 25 minute mark ofindicia 149 as indicated in FIGURE 1, the reference arrow 121 willrotate in a clockwise direction until it reaches the 25 minute mark onindicia 122 when the mechanism will automatically shut off exactly as inthe embodiment shown in FIGURE 2 of U.S. 2,959,646. Control of thewashing operations is identical in both timer constructions;

However, the means by which the auxiliary dry cams 54 and 55 are rotatedrelative to the main dry cams 42 and 41, respectively, varies somewhatin these two embodiments. This will be apparent from an inspection ofFIGURE 3 of U.S. 2,959,646 and FIGURE 2 hereof together with anunderstanding of the detailed mode of operation of the deviceillustrated in the latter figure.

During the rotation of timer drive shaft 36, drive gear 131 rotates inthe same direction and at the same speed due to its fixed connection tothe timer drive shaft 36. Since the ring gear 141 is restrained fromrotation, the planetary pinions 135 are forced to roll around the insideof ring gear 141 with their axes of rotation traveling in the samedirection as that of drive gear 131 even though the actual direction ofrotation of pinions 135 takes place in the opposite direction from thatof drive gear 131. This rotates the cross pins 137 in the same directionas timer drive shaft 36 and causes pinions 136 to move in an identicalfashion to pinions 135 since the adjustable ring gear 145 is restrainedfrom rotation during this period by means of the friction material 15 1pressing against the inside face of adjustable member 145. This causessleeve 45 to rotate in the same direction and at the same speed as timerdrive shaft 36 with the result that no relative rotation takes placebetween the main dry earns 42 and 41 and their respective adjustablecams 54 and 55.

During the setting operations when lever 78 is moved, for example, fromthe position shown in FIGURE 1 back to a 15 minute dry time position,the positions of the secondary cams 54 and 55 relative to main dry cams41 and 42 are identical in both embodiments even though lever 78 wouldhave to be moved only half as far in FIGURE 1 as in FIGURE of U.S.2,959,646 to achieve this change of dry time setting. This is due to theillustrative gearing ratios selected for the embodiment of FIGURE 2.Assuming gear 131 and 133 to have 24 teeth, pinions 135 and 136 to have12 teeth and the ring gears 141 and 145 to have 48 teeth, the reason forthis angular variance between the two embodiments will be readilyunderstood.

For example, a counterclockwise movement of lever 78 in FIGURE 1 willcause a rotation of planetary pinions 136 about the cross pins 137 sincethe nonrotatable ring gear 141 and stationary drive gear 131 (since thetimer drive shaft 36 is always stationary for all practical purposesduring the setting operations) prevents planetary pinions 135 and crosspins 137 from rotating around the axis of the timer drive shaft 36. Therotation of the planetary pinions 136 produces a rotation of the drivengear 133 proportional to the ratio of the number of teeth on theadjustable ring gear 145 to those on driven gear 133. Since this ratiois two to one, it will be seen that a movement of setting lever 78 inFIGURE 1 will produce a 180 movement of the auxiliary cams 54 and 55about the timer drive shaft 36. By merely compressing the dry timesetting scale to a 90 arc, therefore, the same basic operation can beachieved with the device shown in FIGURES 1-3 as in the deviceillustrated in FIGURES 1-10 of U.S. 2,959,646. It should therefore beapparent that all other remarks pertaining to the circuitry, campositioning and general operation of the device illustrated in FIGURESl-10 of U.S. 2,959,646 also apply to the device illustrated in FIGURES13. This includes the means by which the line switch may be opened byaxial movement of timer knob 86 since the entire planetary gear packageis movable with timer shaft 36 during this pre-setting operation.

While lever 78 has been directly attached to the adjustable ring gear145, it should be readily apparent that the dry time setting scale, orindicia 149, as indicated in FIGURE 1, may be expanded to 180 merely byincorporation of a further gear change mechanism between lever 78 andthe adjustable ring gear 145. For example, a gear engageable with theperiphery of the adjustable ring gear and movable by arcuate movement ofa gear segment mounted on lever 78 could be made to produce such amechanism in case it was desired to eliminate the separate dry timesetting indicia 149 and rely entirely upon the dry time portion ofindicia 122 for both setting and indicating functions. Such amodification is considered to be an extension of the teaching of theinstant invention.

The operation of the machine controlled by this timer mechanism isterminated whenever the reference arrow 121 moves to a position oppositeto that portion of the dry time indicia 122 which corresponds to the drytime setting appearing opposite lever 78 in indicia 149.

It will be seen that while a fundamental operation of the devices shownin FIGURES 1-l() of U.S. 2,959,646 and FIGURES 1-3 hereof are basicallyidentical, a much more compact unit is produced in the device shown inFIGURES 1-3. The overall timer assembly is capable of regulating theprogramming of one or more groups of circuits with respect to theprogramming of one or more other groups of circuits. While the preferredselection of the stationary or relatively stationary reaction membersfor the differential gear mechanism is shown in the accompanyingdrawings, it is within the scope of this invention to select otherreaction members to perform the same function of adjusting the relativeangularity between the primary and secondary cams controlling theseparate groups of control circuits.

I claim:

1. In a timer mechanism having a plurality of coaxially rotatable cammembers having predetermined cam profiles thereon for controlling theprogrammed actuation of switch members, the combination of a first cammeans; a second cam means coaxially and rotatably mounted with respectto said first cam means; and a planetary differential meansinterconnecting said first and second cam means including a drive gear,means operatively connecting said drive gear to said first cam means, adriven gear, means operatively connecting said driven gear to saidsecond cam means, carrier means, a first planetary pinion rotatablymounted on said carrier means and meshing With said drive gear, a secondplanetary pinion rotatably mounted on said carrier means and meshingwith said driven gear, a stationary ring gear meshing with said firstplanetary pinion, and an adjustable ring gear means meshing with saidsecond planetary pinion whereby said rotation of the drive gear providesfor rotation of said first and second cam means in unison and angularmovement of said adjustable ring gear means changes the angularrelationship between said first and second cam means. 5

2. The invention in accordance with claim 1 further including a panelmember, indicia means on said panel member, and said adjustable meansbeing in cooperative relationship with said indicia means for indicatingthe relative angular relationship between said first and second 10 cammeans.

References Cited in the file of this patent UNITED STATES PATENTS PeilerDec. 14, Shannon Feb. 13, Dunham July 24, Bliss Aug. 5, Huffman Jan. 10,Vice Mar. 27,

1. IN A TIMER MECHANISM HAVING A PLURALITY OF COAXIALLY ROTATABLE CAMMEMBERS HAVING PREDETERMINED CAM PROFILES THEREON FOR CONTROLLING THEPROGRAMMED ACTUATION OF SWITCH MEMBERS, THE COMBINATION OF A FIRST CAMMEANS; A SECOND CAM MEANS COAXIALLY AND ROTATABLY MOUNTED WITH RESPECTTO SAID FIRST CAM MEANS; AND A PLANETARY DIFFERENTIAL MEANSINTERCONNECTING SAID FIRST AND SECOND CAM MEANS INCLUDING A DRIVE GEAR,MEANS OPERATIVELY CONNECTING SAID DRIVE GEAR TO SAID FIRST CAM MEANS, ADRIVEN GEAR, MEANS OPERATIVELY CONNECTING SAID DRIVEN GEAR TO SAIDSECOND CAM MEANS, CARRIER MEANS, A FIRST PLANETARY PINION ROTATABLYMOUNTED ON SAID CARRIER MEANS AND MESHING WITH SAID DRIVE GEAR, A SECONDPLANETARY PINION ROTATABLY MOUNTED ON SAID CARRIER MEANS AND MESHINGWITH SAID DRIVEN GEAR, A STATIONARY RING GEAR MESHING WITH SAID FIRSTPLANETARY PINION, AND AN ADJUSTABLE RING GEAR MEANS MESHING WITH SAIDSECOND PLANETARY PINION WHEREBY SAID ROTATION OF THE DRIVE GEAR PROVIDESFOR ROTATION OF SAID FIRST AND SECOND CAM MEANS IN UNISON AND ANGULARMOVEMENT OF SAID ADJUSTABLE RING GEAR MEANS FHANGES THE ANGULARRELATIONSHIP BETWEEN SAID FIRST AND SECOND CAM MEANS.